Huffington Post:

A new type of rocket that could send humans to Mars in less than six weeks instead of six months or longer may be one step closer to reality.

NASA has selected Texas-based Ad Astra Rocket Company for a round of funding to help develop the Variable Specific Impulse Magnetoplasma Rocket, or VASIMR. The new rocket uses plasma and magnets, not to lift spacecraft into orbit but to propel them further and faster once they've escaped the planet's atmosphere.

“It is a rocket like no other rocket that you might have seen in the past. It is a plasma rocket," Dr. Franklin Chang-Díaz, a former shuttle astronaut and CEO of Ad Astra said in a video describing the rocket. "The VASIMR engine is not used for launching things into space or landing them back but rather it is used for things already there. We call this ‘in-space propulsion.'"

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